Try using tin cables, they are ultra low voltage but go on for ever, well not literally ever; they last longer, in length, than glass fibre; but glass fibre holds more EU. The tin cables only have to go down 10-15ish blocks to be safe from the windmills generating good power, too.
____________________________________________________________________________
I didn't get to finish my name...
I_Be_A_Troll_That_Lives_Under_The_One_And_Only_Bridge